Purpose:
Graphically examine and record slope (rate of change) values:
- Use an ROI control to select region of interest
- Maximum, minimum, mean, and end-point slope values are reported.
If X column for data is set to type Time, the slope values are reported as "<value>/s"
- 1st derivative of data is displayed. Smooth control for derivative is provided to help with noisy data.
The slider range for smooth points dynamically updates based on noise level in data.
- Store the current slope values to a worksheet.
- Scan entire data by segements using specified ROI width, and save slope values to worksheet
- Switch to previous/next Y column in worksheet to analyze multuiple datasets
- Zoom into data and rescale to full range, for easy exploration
Installation:
Download the file and drg-and-drop onto Origin. A new icon named Slope Analyzer will appear in the Apps Gallery window.
Operation:
Data Selection:
- Select worksheet with desired data, and click on the icon to launch the dialog.
- If you select a particular Y column, the dialog will start with that data.
If no column is selected, data from the 1st Y column is loaded.
- Use the Previous Y Column and Next Y Column buttons to switch to other Y data columns in the worksheet
- When working with time data, first set the X column in worksheet to Time format with desired display format before launching the tool.
Slope Calculation:
- Middle panel shows current data. Bottom panel shows 1st derivative of the data.
- Use the Smooth derivative check box and the slider to apply smoothing to 1st derivative.
This is useful for noisy data. The slider upper limit automatically updates based on noise level when new data is selected.
- Move the ROI rectangle in the middle panel to select subrange of data. The top panel displays the zoomed data and the slope lines.
Use the buttons on the top right of the middle panel to Zoom into data and to Rescale.
Note that you can also hold down the Z/X keys and use the mouse wheel to zoom/pan inside this layer.
- Slope Calculation:
Max Slope: Maximum in 1st derivative within ROI range. The slope line is drawn through the point where the maximum is located.
Min Slope: Minimum in 1st derivative within ROI range. The slope line is drawn through the point where the minimum is located.
Mean Slope: Mean value of 1st derivative within ROI range. The slope line is drawn through the mid point of the ROI range.
End Points Slope: Calculated by connecting the 1st and last points within the ROI range. Line is draw through the two points.
- If X data column in worksheet is set as Time, the slope is reported in units of 1/sec.
Output::
- The Save Slope Values button will write slope values for current ROI data range to output worksheet
- The Scan and Save Slopes button will save slope values for each segment of the data, starting from begining to end, using specified segment width.
- Output book may be behind the dialog. Move dialog to view book.